Study on the relationship between the fitness of three types of N95 respirators and facial dimensions.

N95 respirators are the core equipment used by healthcare workers to prevent the spread of respiratory diseases. The protective effect of N95 against infection spread depends on the fit of the N95 to the wearer, which is related to the wearer's facial dimensions. The purpose of this cross-sectional study was to assess the relationship between the fit of three types of N95 and facial dimensions. A total of 305 healthcare workers from ten hospitals in Beijing were recruited for this study. Facial dimensions of workers were measured using Intel RealSense Depth Camera D435. Fit testing was conducted on three types of N95 using the TSI-8038 Porta Count Pro + Respirator Fit Tester. Possible associations between the fit test results and facial dimension data were examined. A Porta Count reading of 100 was used as the criterion for an acceptable fit. The fit of the folding respirators was positively correlated with nose length (r = 0.13, p = 0.02), nose height (r = 0.14, p = 0.02), and face width (r = 0.12, p = 0.03), whereas that of flat respirators was correlated with nose width (r = 0.16, p < 0.01), chin length (r = 0.18, p < 0.01), and pro-face width (r = 0.13, p = 0.02), and that of arched respirators was correlated with the nose length (r = 0.13, p = 0.03). The fit of N95 for wearers depends on their facial features. The results of this study can provide advice for medical workers to choose the appropriate N95. Medical staff should fully consider their facial dimensions when choosing an appropriate N95 to improve the protective efficacy of respirators and to reduce the risk of infection by respiratory diseases.

Facile Route to Synthesize a Highly Sinterable Li1.3Al0.3Ti1.7(PO4)3 Solid Electrolyte.

NASICON-type Li1.3Al0.3Ti1.7(PO4)3 (LATP) is a widely used solid electrolyte in solid-state lithium batteries, owing to its excellent chemical stability against moisture and high total ionic conductivity. However, traditionally, densification of LATP has been achieved through a high-temperature sintering process (approximately 1000 °C) owing to its poor sinterability. Herein, we report a facile synthesis route to obtain highly sinterable LATP solid electrolyte using tetrabutyl titanate (C16H36O4Ti) as the titanium source and incorporating the traditional solid-state reaction method. The synthetic LATP powder mixed with a low ratio of LiTiPO5 exhibited a hybrid crystalline-amorphous phase structure, which facilitated grain fusion, promoted structural homogeneity, and facilitated structural densification under low-temperature sintering. The sintered LATP pellet, which exhibited an interconnected structure and indistinct grain boundaries, achieved a relative density of >90% and an ionic conductivity of 0.667 mS/cm at a sintering temperature of only 750 °C. Additionally, we systematically studied and demonstrated the synthesis reaction mechanism, sintering behavior, and ionic diffusion kinetics of LATP electrolytes. Our study paves the way for synthesizing highly sinterable LATP solid electrolytes using a simple, additive-free, and cost-effective method.

Time-resolved fluorescence microspheres-antibody-penicillin-binding protein assisted construction of immunochromatographic assay for sensitive detection of 22 ß-lactams in milk.

A sensitive immunochromatographic assay (ICA) using time-resolved fluorescence microspheres (TRFMs) coupled with an indirect-labeling mode was developed for simultaneously determining 22 kinds of ß-lactams in milk samples. The TRFMs labeled anti-receptor monoclonal antibodies (mAbs) conjugated to penicillin-binding proteins (PBPs) as ternary TRFMs-mAb-PBPs (TMP) nanoscaffolds provide excellent solubility, brightness, and stability. Thanks to the fact that they not only fully expose the binding sites of PBPs, thereby enhancing the biological affinity of PBPs towards the target, but also generated superb fluorescence signals, the versatile TMP manifested unique possibilities as efficient probes for ICA with remarkable enhancement in sensitivity in ß-lactams screening. The results showed that the standard curves of the 22 varying ß-lactams displayed linearity in their respective concentration ranges (R2 > 0.98), with the cutoff values of 1-100 ng/mL. The constructed TMP-ICA was successfully applied to the analysis of real milk, with consistent results compared with liquid chromatography-tandem mass spectrometry (LC-MS), providing an effective method for sensing ß-lactams in food matrices.

Insights into the Effects of Co-Regulated Factors on Li1.3Al0.3Ti1.7(PO4)3 Solid Electrolyte Preparation: Sources, Calcination Temperatures, and Sintering Temperatures.

The ionic conductivity, phase components, and microstructures of LATP depend on its synthesis process. However, their relative importance and their interactions with synthesis process parameters (such as source materials, calcination temperature, and sintering temperature) remain unclear. In this work, different source materials were used to prepare LATP via the solid-state reaction method under different calcination and sintering temperatures, and an analysis via orthogonal experiments and machine learning was used to systematically study the effects of the process parameters. Sintering temperatures had the greatest effect on the total ionic conductivity of LATP pellets, followed by the sources and calcination temperatures. Sources, as the foundational factors, directly determine the composition of a major secondary phase of LATP pellets, which influences the whole process. The calcination temperature had limited impact on the ion conductivity of LATP pellets if pellets were sintered under the optimal temperature. The sintering temperature is the most important factor that influences the ion conductivity by eliminating most secondary phases and altering the microstructure of LATP, including the intergranular contact, grain size, relative densities, etc. This work offers a novel perspective to comprehend the synthesis of solid-state electrolytes beyond LATP.

Low-Temperature In Situ Lithiation Construction of a Lithiophilic Particle-Selective Interlayer for Solid-State Lithium Metal Batteries.

Unexpected interface resistance and lithium dendrite puncture hinder the application of garnet-type solid-state electrolytes in high-energy-density systems. Different from the previous high-temperature (>180 °C) molten lithium that promotes the alloying reaction between the coating layer and Li to enhance the interface contact, herein, we introduce liquid-metal-like SbCl3 to construct a three-dimensional Li+ directional-selection interlayer by in situ low-temperature lithiation (80 °C). An interlayer with a more negative interface energy composed of SbLi3 and LiCl exhibits a superior affinity with Li and LGLZO, which reduces the interface resistance and suppresses the growth of Li dendrites by an insulated electron. The introduction of the SbCl3 modification layer into Li/Li symmetric cells enables charge/discharge at a current density of 6.0 mA cm-2 and operation for more than 1000 h under 2.0 mA cm-2 at room temperature. The full cells with the LiFePO4 cathode exhibit a high residual capacity of 144.8 mAh g-1 at 0.5 C after 1000 cycles and excellent cycling stability with a retention ratio of 94.7% at 1 C after 600 cycles. The low-temperature lithiation method based on an energy-saving perspective should be applied to other types of solid-state electrolyte modification strategies.

EAG responses of Apis cerana to floral compounds of a biodiesel plant, Jatropha curcas (Euphorbiaceae).

The Eastern honey bee, [Apis cerana (F.)], is an important and common pollinator for an important biodiesel tree, [Jatropha curcas (L.)]. To understand sensitivity of A. cerana to different floral compounds, we quantified volatile floral compounds of J. curcas, then determined electroantennogram (EAG) responses of A. cerana to 11 compounds each at five doses (0.4, 4, 40, 400, and 4,000 microg) of six most active floral compounds. Our results demonstrated that floral compounds of J. curcas differ in variety and quantity while linalool is always a major constituent in floral blends from three different plantations. Antennae of A. cerana responded to all 11 floral compounds, implying a broad sensitivity of A. cerana to different floral compounds of J. curcas. Antennae of A. cerana were most sensitive to six compounds, including all aldehydes (decanal, hexanal, nonanal, and octanal), linalool, and an alcohol (3-hexenol), suggesting that A. cerana possesses chemoreceptors to aldehydes, linalool, and alcohol on the antenna. Furthermore, low doses elicited a zero EAG response and high doses a positive one under all of six most active compounds. Thus, EAG responses of A. cerana were both chemical specific and dose-dependent. Our results here suggest that A. cerana is senstive to various floral compounds, and linalool in the floral blends of J. curcas plays a key role to attract A. cerana.